The Global Positioning System (GPS) is very well known as a mechanism for providing relatively accurate positioning information using small portable devices. To create a remote tracking device useful for tracking or monitoring persons GPS devices need a mechanism to transmit the location information from the GPS to a central site where a record of the person's location can be maintained. There have been several devices that have used terrestrial wireless or cellular networks coupled to a GPS engine to transmit the location data to a central repository. The GPS/cellular device can either transmit the raw GPS data over the cellular network to a central system which can then process the GPS data to determine the location of the device, or if enough processing power is built into the remote tracking device the GPS calculations can be done on the remote tracking device and the derived location information can be transmitted to the central repository. A time stamp can be associated with the location information to provide temporal context for the location information.
An example of such a device is described in U.S. Pat. No. 6,014,080 to Layson, Jr. The remote tracking device of Layson, Jr. includes a tamper resistant strap and housing which holds a GPS engine and a wireless data modem. The remote tracking device communicates with a central station computer using the wireless data modem and transmits the location data for the remote tracking device. The central station includes a computer which is operable to take the position information from the remote tracking device and to compare that location information against a schedule of rules and location restraints to determine if the remote tracking device has strayed from a permitted inclusion zone or has entered a forbidden exclusion zone.
Another remote tracking device is described in U.S. Pat. No. 6,072,396 to Gaukel. The remote tracking device of Gaukel is a two-piece device with a tamper resistant unit securely attached to the person to be monitored. The secure unit is connected to, or in communication with, a body-worn device that includes a GPS engine and a cellular modem. As with Layson, Jr., the cellular modem is used to communicate the location information from the GPS engine to a control station.
Yet another remote tracking device and system is described by U.S. Pat. No. 5,867,103 to Taylor, Jr. The remote tracking device of Taylor, Jr. includes a tamper detection mechanism, a mechanism for receiving a signal from a positioning device, such as a GPS satellite, and a transmitter for transmitting a signal to a central station. The system for monitoring the remote devices includes a position determining mechanism for computationally determining the location of the remote device based on the signal from the positioning device and a temporal marking mechanism for providing a time stamp associated with the location determination.
While each of these devices shares a similar use of GPS and cellular or wireless data technology to gather information about the position of the remote device and to transmit information about the position to a central computer, each of these devices also suffer from the same deficiencies. Examples of these deficiencies are the lack of an ability to do anything with the information once it is received at the central computer. At most the central computers of these devices can generate messages of rules violations that can be transmitted to a parole officer or other recipient. The systems do not provide for any context for the message about the violation and do not provide for computer access to information about the remote tracking device and any violations or a monitoring center which can be contacted by the remote tracking device and the parole officer or other supervisor who has responsibility for the person being monitored.
These systems pass all location data obtained from the tracking devices directly through to the parole officer or supervisor has responsibility for the person being monitored. This places the task of sorting through the mountain of location data directly on the parole officer or supervisor who may be in charge of a great number of persons being monitored. Placing such a heavy burden on the parole office or supervisor is generally undesirable and a waste of resources.
Further, these systems do not allow for voice communication with the person wearing the remote monitoring device. Some of the devices described above can initiate tones or vibrations in the device in the event of a rules violation, but none have the ability to initiate voice communication between the person being monitored and personnel at a monitoring center or the persons parole officer or supervisor.
Still further, these devices to not have any type of alarm system, alarm management, or alarm hierarchy which can be used to warn the person being monitored, or, as a last resort, warn those in the vicinity of the person being monitored that a violation is occurring.